She’s been locked in a messy custody battle with ex-fiancé Levi Johnston and finally Bristol Palin has been granted primary custody of their son Tripp.

According to Radar, the 23-year-old single mom defended her right to physical custody after Johnston filed for shared rights last October, however it seems Levi didn’t have a chance given his track record.

He's never been one to keep secrets, and now Bristol Palin's ex, Levi Johnston is letting it all out in his new book "Deer in the Headlights: My Life in Sarah Palin's Crosshairs" out September 20.

According to the tell-all, Bristol was so angered by her mother, former Alaska Governor Sarah Palin's 2008 pregnancy with her Trig, that she actually convinced the Playgirl to get her pregnant as revenge a month before her mom's due date.